1. Technical Field of the Invention
The embodiments of the invention relate to storage circuits and, more particularly, to a scheme to switch a data FIFO device between strobe sources.
2. Description of Related Art
Generally, when data acquisition entails the input of data from a data source of one domain and transfer of that data into a second domain, some mechanism may be employed to operate as an interim transfer mechanism or an interface between the data source and destination. The data interface medium may be in the form of flip-flops, latches, buffers, registers, memories, etc. In one instance, a data FIFO (first-in, first-out) unit may be utilized to receive the data from one operating domain and to output the data based on a timing associated with a second domain. In one example, data from a memory device is sourced to a FIFO unit under control of strobe signals that operate with the corresponding timing signals associated with the memory device. Typically, the timing strobes utilized for clocking the data into the FIFO unit correspond to the particular memory device operably coupled to the FIFO unit to transmit the data to the FIFO unit.
In practice, when a particular memory device is selected for use as a data storage medium for a system, the memory device may have certain attributes to operate within the system. Thus, a processor, bus, memory controller, and/or other devices may dictate a particular type of memory to be utilized within the system. Or, alternatively, a particular memory is chosen and its attributes are employed to configure the system which operates with that particular memory. For example, if a particular memory employs an 8-bit data transfer for a strobe, then the system is generally configured to operate to accommodate the 8-bits per strobe. However, if the particular memory operates using a 9-bit data transfer scheme, then 9 bits of data are transferred for a given strobe and the system is configured to operate to accommodate the 9-bit bus.
In a typical application, a given system employs one type of memory configuration. In the above example, the system may operate with either an 8-bit data transfer per strobe or a 9-bit data transfer per strobe for data transfer from memory. It would be advantageous to have a flexible system, so that the system may operate with different strobing configurations to allow different types of memory devices to be selected and/or employed to operate within the system.